Release mechanism using two retractable piston actuators



V RELEASE MECHANISM USING TWO RETRACTABLE PISTON ACTUATORS Filed Jun 12,i969 1 4 K. CHAIMSQN Sheets+Sheet 1 FIG. I

INVENTOR ROBERT K. CHAIMS'O/V Dec. 15, 1970 K, cH l sofl v 3,546,949

RELEASE MECHANISM USING TWO RETRACTABLE PISTON ACTUATORS Filed June 12,1969 2 Sheets-Sheet 2 INVENTOR ROBERT K. CHA/MSON BYWAA Z A" NT M gdiwwUnited States Patent O ABSTRACT OF THE DISCLOSURE This invention isdirected to a release mechanism for a rod used in a coronagraph or anyother type spring loaded device. The release mechanism makes use of apivotal lever which is held in place by two separate electricallyreleased pistons which are used in case one has.

a niisfire, then the other can be fired. When one piston release isfired the pivotal lever pivots by the unfired piston and releases thespring loaded rod.

STATEMENT OF GOVERNMENT INTEREST The invention described herein may bemanufactured and used by or for the Government of the United States ofAmerica for governmental purposes without the pay ment of any royaltiesthereon or therefor.

BACKGROUND OF THE INVENTION This inventon relates to release mechanismsand more particularly toa release mechanism including two elecv tricallyfired release mechanisms such as squibs either of which may release thedevice held in place by the two electrically fired release mechanisms.

Heretofore, spring loaded rods and other devices have been held in placeby a single release mechanism. If a device is held in place by a singlerelease mechanism, and the single mechanism does not operate, then thedevice will not release. Such devices used for remote control such aselectrically fired release mechanisms on satellites or rocket borneinstruments will bring about a failure if the single release mechanismfails. Some release mechanisms are provided with two electrical controlcircuits connected with a single unit, however, the problem may not beentirely electrical and the device fails to release. Therefore, it isnecessary that two different release mechanisms be used to avoid failurein the event one of the release mechanisms fails.

SUMMARY OF THE INVENTION This invention is directed to a system whichmakes use of two separate electrically fired release mechanismsincluding movable pistons to hold a single spring loaded rod orany othermovable device in place for release by remote control. A spring loadedrod is provided with a pivotably mounted somewhat T-shaped lever whichholds the spring loaded rod in place by use of two separate electricallyfired powder driven pistons or any other operable holding mechanisms.The pistons lie in front of the T-shaped lever to hold the rod in placefor release by either of the electrically fired powder driven pistons.When either of the electrically fired pistons are released, the T-shapedlever pivots about the pivot point and moves around the piston that isnot fired. In the event one piston does not release, the other pistonmay be released to insure release of the spring loaded rod. Theinvention provides a release mechanism which releases a spring loadeddevice regardless of which release piston is actuated. In the event onerelease piston does not function, the other one is available and canrelease the spring loaded device.

3,546,949 Patented Dec. 15, 1970 STATEMENT OF THE OBJECTS It istherefore an object of the present invention to provide a double controlrelease mechanism for releasing a spring loaded device by actuation ofeither control mechanism.

Another object is to provide a duo-control release mechanism whichprovides an increased reliability for release of a spring loaded deviceby remote control.

Still another object is to provide a simple release mechanism forproviding increased reliability against failure of operation.

While still another object is to provide increased reliability againstfailure of a release mechanism with very little additional weight due tothe increased reliability.

Other objects and advantages of the invention will hereinafter becomemore fully apparent from the following description of the drawing.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side view partially insection to more clearly illustrate some of the elements.

FIG. 2 is a top view partially in section to more clearly illustrate therelationship of some of the elements.

FIG. 3 is a rear view illustrating some of the elements.

DETAILED DESCRIPTION Now refering to the drawings there is shown byillustration a release mechanism including a spring loaded rod 11 heldin place by two separate members 12 and 13 such as separately firedsquibs each including a powder driven piston 14. The squibs are held inplace by a plate 20. The rod 11 is mounted for movement in a frame 15which is shown in its simplest form since the release mechanism is theimportant element of concern. The electrically operated releasemechanisms are mounted onto the frame in a separate housing 16 in spacedrelationship such that the retractable pistons 14 operate in parallelrelationship with each other and with the frame to which the releasemechanisms are mounted.

The end of the rod which is held by the release mechanisms has a slot 17therein for reception of a somewhat T-shaped lever 18. The lever issecured at once end to the rod by a pin 19 about which the lever ispermitted to pivot. The pin 19 also secures a rod support 21 in placeabout the rod, the purpose of which will be explained later. The freeend of the T-shaped lever is formed with a smooth surface which includesa slight indentation 23 near the ends of the T-end. The frame isprovided with an aperture 24 of sufficient size for the end of the rodto pass and a slot 25 in cooperation with the aperture for passage ofthe T-shaped end of the lever. A spring 26 is illustrated as beingassembled around the rod between the rod support 21 and the frame inorder to force the rod outwardly when held in place and released by oneof the release mechanisms. The support aids in aligning the rod and alsoacts as a stop when the rod has been extended the desired distance tothe fixed support 28. The support has Teflon feet 27 thereon which aidsthe support in its movement on the frame.

In the operation of the release mechanism, the rod is forced backagainst the spring such that the forward face 22 of the T-shaped leveris beyond the frame. The retractable pistons are assembled such that theends of the pistons are supported in their housing with the lower endsbelow the position of the T-shaped end of the lever and in front of face22. The rod is permitted to move forward such that the T-shaped end ofthe lever is held behind the retractable pistons will hold the rod inplace against the compressional force of the spring. The loaded rod isnow in a retracted position and ready for release to its extendedposition for the desired use.

The retractable pistons are connected into separate electrical circuitssuch that an electrical current flow through each of the separaterelease mechanisms will permit or force the pistons to be retractedseparately independently of each other.

For release of the rod, an electrical current is passed through one ofthe release mechanisms activating the squib thereby forcing theretractable piston to be retracted. Upon retraction, the pivota'blelever will be freed by the retracted piston for movement relativethereto. Since the lever is positioned behind both retractable pistons,release by one retractable piston permits the lever to move over aboutits pivot such that the T-shaped end will be free of the piston whichhas not been retracted. Therefore, the spring will force the rod intoits unloaded position.

Now lets suppose that the electrical circuit to release mechanism 12 isactuated and nothing happens, that is, for some reason the releasepiston is not retracted, then the rod is not released. Since releasemechanism 13 is available, the electrical circuit to release mechanism13 is actuated. Upon retraction, the T-shaped lever will be released andthe rod will be forced into its desired position by spring action.Therefore, it is important to have separate release mechanisms as wellas separate electrical circuits especially when the device is remotelycontrolled such as in a satellite or on a rocket flight.

The squibs used may be of any type in which the piston is normally in anextended position and when fired by an electrical discharge, the pistonis retracted. Since the T- shaped lever is pivoted at the end, removedfrom the squibs, retraction of either squib permits the lever to moveabout its pivot sufficiently to pass the squib piston which has not beenretracted. Therefore, the spring loaded rod will be released regardlessof which piston is retracted. Since there are two squibs, a misfire ofone squib will not be fatal unless, of course, both squibs do not fire.Thus, the arrangement shown will provide a system which should 4 workeverytime by release of at least one of the retractable pistons holdingthe spring loaded rod in place.

The system has been described as useful for a spring loaded rod which isreleased to be moved into place. The system may be used for any deviceheld in place by a release mechanism especially for remote control by adirect electrical connection or by a radio signal which actuates anelectrical circuit which activates the release mechanism.

What is claimed and desired to be secured by Letters Patent of theUnited States is:

1. A release means for holding a spring loaded device in a containedposition relative to a base and subsequently release said device formovement by the spring to a different position; which comprises,

first and second release mechanisms positioned relative to each other inparallelism,

each of said first and second release mechanisms including an extendedmovable piston,

a T-shaped pivotable lever supported by said device,

said extended movable pistons of said first and second releasemechanisms cooperating with said T-shaped pivotable lever and with eachother to position said device in a contained position.

whereby actuation of either of said first or second release mechanismsto retract its piston will release said T-shaped lever and said devicefrom its contained position.

2. A release means as claimed in claim 1; wherein,

each of said release mechanisms has electrically operated means toretract its piston.

References Cited UNITED STATES PATENTS 1,208,863 12/1916 Waldow 7422,978,911 4/1961 Haessler 742 MILTON KAUFMAN, Primary Examiner

